Hello Nagendra,
  It is good to hear that you are going in interesting field.Nowadays MBA is streaming good.
  As per your choice and comfortable you can select your college
   The top colleges are here

1. IIM Bangalore
2. IIIM Calcutta
3.IIIM  Ahemadabad
4. IIM LUCKNOW
5. IIM Kharagpur
6. Xavier school of management,shamsedpur

Hope this helps you
All the best dear!

If you want to be a General Manager you can opt for MBA in in marketing or operations. Since you are a mechanical engineer operations MBA will help you in in running the company efficiently and cutting costs of producing and selling goods. You can also go for strategy e as a specialisation in MBA which is available in only the top colleges of India. Give CAT exam score well in it try to get into IIM and you can easily get into general management role in one of the top industry companies